Preparation Of Polymer-inorganic Semiconductor Composites And Their Photocatalytic Performance

With the development of economy and society,it is necessary for us to realize the sustainable development of society.Energy shortage and environmental pollution are seriously problems to hamper the sustainable development.Therefore,looking for clean energies and the approaches of decreasing pollution have become the vital factor of the current scientific research.Semiconductor photocatalytic technology,a kind of green technology,provides a new method to solve the problem of environmental pollution.This method can effectively utilize solar energy to degrade the pollutants.In recent years,iodine bismuth oxide(Bi OI)aroused wide attention by researchers due to its special layer structure and remarkable catalytic activity.However,Bi OI presents a low electrical conduction and rapid photoelectron depletion,exhibiting an inefficient photon harvesting and a low photocatalytic activity.Herein,we investigate on and design a novel photocatalytic reactor for enhanced photocatalysis.(1)Using acid-doped polyaniline(PANI)as raw material,we prepared different mass ratio of polyaniline(PANI)/ Bi OI composite under room temperature.The composite materials were characterized by powder X-ray diffraction(XRD),field-emission scanning electron microscopy(SEM),UV-vis diffuse(UV-vis)reflectance spectra and photoluminescence emission spectra(PL).We investigated the effects of different mass ratio of PANI/Bi OI composite on the degradation of rhodamine B under visible light.The results showed that the photocatalytic activity of PANI/Bi OI is higher than that of pure Bi OI,and PANI/Bi OI(12.5 wt%)showed best photocatalytic activity under the irradiation(800 W Xenon lamp)for 140 min.(2)With Bi(NO3)3·5H2O and KI as raw materials,distinct morphology of Bi OI was prepared by adjusting the amount of PVP in the process of hydrolysis at room temperature.The XRD pattern showed all the reflections can be perfectly indexed as cubic Bi OI.Then we used the SEM,UV-Vis reflectance spectra and PL method to characterize Bi OI material in terms of structure,morphology,light intensity,and the optical absorption features.he photocatalytic testing demonstrated that Bi OI,prepared by adding 0.2 g of PVP,exhibited excellent catalytic performance.(3)We designed a kind of all-weather fixed bed coupled photocatalytic reaction device.This device includes inlet,waterproof switch,impeller,filter and port,UV lamp,photocatalyst adsorbent coupling layer,circulating cooling water,outlet,sealed aluminium acid battery and solar panels.The device's advantages lie in two aspects.On the one hand,solar energy can be stored to achieve all-weather light,improving the effective utilization of natural light;On the other hand,the fixed bed coupled layer is benefial to the improvement of the catalyst utilization efficiency.Finally,we deduced,by means of calculation of a series of mathematical models,the best size of the photocatalytic reactor with a radius of 7 cm and a optimal distance to the coupled layer of 4 cm.